Do not replace stdout in child worker process.

Unidentified spurious problems on Solaris 9, with file descriptor 0
*not* corresponding to stdin, triggered me to change the worker child to
not close its stdout and replace it with the dup()ed pipe
descriptor. Instead, it now fprintf()s directly to that pipe.

Didn't fix the problem on Solaris (still investigating) but still its a
good change.
pthread_cond_timedwait() takes absolute time

Also fix threads actually delivering the signal when they should.
This fixes test failure on Solaris.
mark tests as test_suppress_fail
Merge pull request #1779 from MatthewCattell/solaris10-acceptance-failures

mark tests as test_suppress_fail
Revert "mark tests as test_suppress_fail"
Merge pull request #1781 from cfengine/revert-1779-solaris10-acceptance-failures

Revert "mark tests as test_suppress_fail"
Using high precision clock should avoid corner case...

where time(NULL) returns e.g. 5, but time is 5.99.
Thanks to @kacfengine for spotting this.
Suppress some acceptance tests on solaris 10
Merge pull request #1778 from jimis/lastseen_threaded_load_fix-redmine6103

Lastseen threaded load fix redmine6103
Redmine#5209: string_downcase the eval result for AIX and Solaris
Redmine#6220: on Solaris 10 acceptance tests, use a Perl sort to enable 10_files/02_maintain/changes_depth_search.cf